oapen



(No Model.) 3 Sheets-Sheet 2. T. W. CAPEN.

CRANE.

No. 271.311. Patented Ja;11.30, 1883.

- l N V E N T0 R T/zamaa", W Cape/z. By k s .dttorneys lUNiTED STATES?ATENT OFFICE.

THOMAS W. CAPEN, OF STAMFORD, CONNECTICUT, ASSIGNOR TO THE YALE LOOKMANUFACTURING COMPANY, OF SAME PLACE.

CRANE.

SFECIFIGATION forming part of Letters Patent No. 271,311, dated January30, 1883.

Application filed November 28, 1882. (No model.)

To all whom it may concern:

Be it known that I, THOMAS Wu CAPEN, of Stamford, in the county ofFaireld and State of Connecticut, have invented certain new and usefulImprovements in Cranes, of which the following is aspeciticatiomreferenee being had to the accompanying drawings.

The object of one part of my invention is to prevent the crawling ofa'trolley ot' a crane 1o when the load is being hoisted; and the objectof another part of my invention is to prevent running dow'n of the load.My invention therefore consistsin a locking mechanism for a trolley, andin a brake mechanism applied, in

r 5 connection with the hoisting apparatus, to prevent ruiming down ofthe load.

In the accompanying drawings, Figure lis a side elevation of ajib-cranewith myimprovements applied. Fig. l is an elevation partly zo insection, with the hoisting-chains omitted to show the trolley holdingrope. Fig. 2 is a rear end elevation of the same. Fig. 3 is an enlargedview of part of my trolley locking mechanism detached. Fig. 4 is avertical section of the same on the line et 4 of Fig. 3. Fig. 5 shows anautomatic brake mechanism to prevent the load from running down. Figs. 6and 7 are details of the same, showing parts detached.

Thejib-crane and its operating mechanism are of the kind set forth in myUnited States Patent No. 242,271, granted May 3l, 1881, and need nottherefore be described in detail.

In connection with the trolley A, I provide a trolley holding rope orcable, B, secured at its opposite ends to the trolley at C, passing overguide-sheavesDandE,downaroundthedouble grooved sheave F, thence up overthe sheave G, thencedownaround theotherpartofthe doublegrooved sheave F,thence up over the guidesheave H to the trolley, thus formingpractically an endless band to which the trolley is attached. 'SheavesD, E, and lEI are on the same shafts that carry the chain-wheels of theoperating-chain X2, as appears by the drawings, and these sheaves areloose upon those shafts,

so as to turn freely, or to stand at rest independently of the shafts.The double-grooved sheave F is secured loosely upon a shaft, I, which isan eccentric extension from the short shaft K.

l This extension passes eccentrcally through another shaft, L, and thehand-wheel M (or it may be a lever) and shaft L and thel shaft I aresecured together by means of a bolt, N, or otherwise. The result is thatby rotating the hand-wheel the shaft Iand the double-grooved sheave Fwill be raised and lowered, and will consequently either strain orloosen the cable B. The annular grooves in the sheave F aropreferablymade V-shaped, as illustrated, so that when the sheave is lowered therope will in a measure wedge into the grooves, and they will grip itfirmly. The number of sheaves and number of turns in the endless cablemay be varied, and I might use a single-grooved sheave F. However, adouble-grooved sheave is much preferable, because theV friction on thecable B is doubled and the movement 'of the eccentric slackens the ropetwice as much as y with a single sheave. This is advantageous, becausewhen the trolley is to move itis necessary that the cable should passfreely over the sheave. I bevel the outside edges of the sheave F at att, as shownin Fig. et, and provide a correspondingly beveledbrake-block, P, to en'- gage with the beveled edges of the sheave. Whenthe shaft I and sheave F are thrust downward to bring the rope B taut,so that it will not slip, the brake-block engages with the sheave at thesame instant and prevents the sheave from turning. The operator canalways, therefore, conveniently stop theA trolley and hold it securelyin any position upon its track. The sheave G operates as an adjustingdevice, being attached to the frame by means ot' a'serew-bolt, X, sothat by turning the nut on the screw the rope B may be tightened orloosened, as desired.

Referring, now, to my brake for the hoisting will say that it issimilarin principle to thatdescribed and claimed in my United StatesPatent No. 263,479, granted August 29, 1882. Upon the shaft Q of thehoisting mechanism l Through the shaft runs a metallic cross-key,preferably steel, which projects from opposite sides of the shaft, asshown in Fig. 7, and is located between the loose collar and the loosemechanism,as illustrated'in Figs. 5, 6, and 7, I

provide a loose worm, R, and aloose collar, S.

worm. l The collar and the worm are each provided with lugs T withinclined adjacent faces standing normally in the rotary path ot' theprojections U ofthecross-key. When the shaft is turned in eitherdirection these projections impinge againstthe lugs T of the collar andworm and cause them to turn with the shaft, preserving their relativepositions, as' illustrated in Fig. 5. If, however, when a load is on thecrane, there is a tendency to turn the worm-wheel (not illustrated, butto be the same as shown in my last-mentioned patent) and the worm, thelatter will move independently of the loose collar and shaft' Q, and theresult will be that the lugs T of the worm will mount the lugs of thecollar and cause apinch, which will drive the extreme bearing ends ofthe worm and collar against the surfaces of the 'hearing U at the pointsV and W and stop all motion. It will thus be seen that whenever theshaft Q is turned normally, so as to operate in the usual manner, therewill be no locking; but whenever the weightrof the suspended loadoperating upon the worm-wheel and worm causes them Vto turn hy theruiming down of the load,locking will instantly take place automaticallyto stop the running down. This form of brake is equally applicable tocranes or hoists where spur-gearing is used,in which latter case a loosepinion would take the place ofthe loose worm with exactly similarresults.

Having thus described my improvements, what I claim as new, and desireto secure by ALetters Patent of the United States, is-

1. The combination, with the trolley, of an endless rope or cable towhich the trolley is.

secured, and a brake mechanism for stopping and holding; the trolley bythe aid ofthe cable, substantially as described.

2. The combination of the trolley, the endless cable, the sheaves, thebrake-block, and the hand'wheel or lever, substantially as described.

3. The combination, with the hoisting mechanism, of the shaft Q, theVloose worm, the loose collar, the cross-key projecting between them,andl the lugs with inclined adjacent faces in the rotary path of theprojecting ends of the cross-key, substantially as described.

4. In combination with a brakerope or cable, a double-grooved sheave, F,whereby the action of the eccentric is rendered more el'ective,substantially as described.

5. In combination with a brake rope or cable, an adjusting device,substantially as described.

6. The combination of the eccentric shaft I, the sheave F, the cable B,and the brake-block` P, so constructed that when the eccentric is turnedthe rope is gripped by the sheave F and thc sheave is gripped by thebrake-block, substantially as described.

In testimony whereof I have hereunto subscribed my name this 25th day ofNovember, A. D. 1832.

